There are multiple problems with the script currently used in "run show configuration commands" and the "| commands" conf mode pipe.

First, it uses XorpConfigParser, which was never capable of fully supporting the current config format to begin with. From this come two user-visible problems.
It quotes tag node values that never needs quoting and it simply ignores node comments.

It also can only operate on files, so even in pipe mode it first saves the data from stdin to a temporary file and then opens it. That's also down to the XorpConfigParser API.